Automatic apparatus for electro plating pipe and conduits



Sept. 30, 1958 F. J. KENNEDY 5 AUTOMATIC APPARATUS FOR ELECTRO PLATING PIPE AND CONDUITSv Original Filed Dec. 15, 1950 6 Sheets-Sheet 1 Sept. 30, 1958 J, KENNEDY 7 2,854,395-

AUTOMATIC APPARATUS FOR ELECTRO PLATING PIPE AND CONDUITS firiginal Filed Dec. 15, 1950 6 Sheets-Sheet 2 INVENTOR.

a 7- TOPA/J rs.

Sept. 30, 1958 F. J. KENNEDY 2,854,395

AUTOMATIC APPARATUS FOR ELECTRO PLATING PIPE AND CONDUITS e Sheets-Shee t s I K ffllfjlfl Original Filed Dec. 15, 1950 INVENTOR. 'XNNM BY A v mm a $4 I arr-olefin:

Sept. 30, 1958 F. J. KENNEDY 2,854,395

AUTOMATIC APPARATUS F OR ELECTRO PLATING PIPE AND CONDUITS Original Filed Dec. 15, 1950 6 Sheets-Sheet 4 INVENTOR. K \&m-v\

ept 30, 1958 2,854,395

AUTOMATIC APPARATUS FOR' ELECTRO PLATING PIPE AND CONDUITS F. J. KENNEDY 3=igingl Filed Dec;

6 Sheets-Sheet 5 AUTOMATIC APPARATUS FOR ELECTRO PLATING PIPE AND CONDUITS Qflgingl Filed Dec.

Set, 3, 1958 F. J. KENNEDY 6 Sheets-Sheet 6 a 7-7-0242 rs United States Patent AUTOMATIC APPARATUS FOR ELECTRO PLATHNG PIPE AND CONDUITS Frank J. Kennedy, Mount Lebanon, Pa., assignor to National Electric Products Corporation, Pittsburgh, Pa., a corporation of Delaware Original application December 15, 1950, Serial No. 200,968, now Patent No. 2,675,813, dated April 20, 1954. Divided and this application March 29,1954, :Serial No. 419,242

2 Claims. (Cl. 204-202) This invention relates to apparatus for applying a protective coating by depositing metal on the surface of electric conduits. In its preferred embodiment, the apparatus applies a coating of zinc to steel conduits.

The galvanizing of steel pipe and conduits, especially when the zinc is deposited electrolytically, provides one of the best means for protecting the steel pipes against deterioration. It is an object of this invention to provide improved apparatus for applying such a coating, or other coatings if desired, to steel pipes and conduits.

The invention is especially concerned'with a construction of the conduit handling and conveying mechanism in such a way as to transmit the necessary electric currents to the conduits effectively and etliciently and without the usual deterioration of the apparatus which accompanies the use of electrolytes and plating currents.

One feature of the invention relates to a construction in which the portions of the pipe supports, which extend into the electrolyte, are protected from the electric current by insulation. In the preferred construction, most of the uninsulated surface of the conduit supports, which is submerged in the electrolyte, is enclosed within the conduit. The construction prevents passage of current between the electrolyte and the surfaces of the conduit support which are at a substantial distance from the conduit.

Another feature of the invention relates to a construction in which the electroplating current is transmitted to the conduit supports through bus bars which also serve as the guides for holding the conduit supports in operative position during the passage of conduits through the electrolyte. This construction makes it possible to use the full pressure between the bus bars and the moving contacts for holding the conduit supports against the conduits. This provides a combination in whichthe current is supplied to the conduits during the portion of their travel when current is required, and the holding pressure is terminated at the regions where the conduits are passing into or out of the electrolyte and the supports must move with respect to the conduits for either gripping or releasing them depending upon the particular end of the apparatus at which the supports are located at the time.

This application is a division of my copending application, Serial No. 200,968, filed December 15, 1950, now Patent No. 2,675,813, dated April 20, 1954. The parent application contains claims to the portions of the apparatus which convey the pipe through the electrolyte, but no claims to electrical features of the apparatus are contained in the parent case. This application has been filed to include the electrical features of the apparatus.

Other objects, features and advantages of the invention will appear or be pointed out as the description proceeds.

The preferred embodiment of the invention is illus- Patented Sept. 30, 1958 trated in the accompanying drawings of which Fig. l is a plan view of the electroplating tank and the conveying apparatus; Fig. 2 is a vertical section along lines IIII of Fig. 1, there being certain details of construction omitted for purposes of clarity; Fig. 3 an enlarged transverse vertical section along lines III-J11 of Fig. 1; Figs. 4 and 5 still further enlarged end and side views, respectively, of one of the pipe-carrying arms and its supporting members; and Figs. 6 and 7 enlarged end and side views, respectively, of the aim loading mechanism provided by the invention.

Referring initially to Figs. 2 and 3, the bath is contained in an open-topped, metal tank 1 formed of side walls 2 and 3, end walls 4 and 6 and a bottom 7, the bottom being supported by transversely extending I-bearns 8.

Pipe 10, which is to be plated, or galvanized, is carried by a crane (not shown) from a previous pipe-treating bath onto a roll-down, pipe-feeding table 11 (Fig. 2), from which it rolls onto an endless, looped rack conveyor 12, to be described later, there being suitable stops 13 and 14 and pipe guiding members 16 to regulate and insure proper delivery of the pipe to this conveyor.

From the rack conveyor the individual lengths of pipe each are picked up and carried through and out of the bath by the conveying mechanisms which form an important part of this invention, and which generally considered, include pipe-carrying arms 17 and 18 (Figs. 3, 4 and 5) the lower ends of which are formedas inwardly projecting fingers 19 and 21 adapted to be thrust into the ends of the pipe as the pipe is being carried by rack conveyor 12; the fingers subsequently being pressed-out of pipe end engagement at the discharge end of the tank.

The location at which the pipes are connected to the arms 17 and 18 is the loading station of the apparatus. These arms 1'7 and 18 mount rollers 22 that ride on a pair of endless tracks 23 and 24 which run longitudinally along each side wall of the tank, each of the tracks paralleling one another in a course designed to cause the arms to move downwardly past their loading station (Fig. 2) and then to cause the fingers 17 and 18 and the pipe supported by them to dip into the galvanizing bath. Following this, the course of the tracks runs horizontally to cause the pipe to be moved through the bath, then upwardly to effect removal of the pipe from the bath. As contemplated, the arms release the pipe during their upward movement, and then the tracks loop back horizontally to cause the arms to be returned to their loading zone. For purposes of description, the downwardly inclined extents of the tracks are termed A (Fig. 2), the horizontal galvanizing extents B, the upward pipe-removing extents C and the horizontal arm-return extents D, the return extents D running for the most part, outside of the tank side walls 2 and 3, while extents A, B and C are within the vertical planes of these side walls.

From the above, it will be recognized that each track mounts a series of longitudinally spaced arms 17 and 13, the spacing being such that transversely aligned pairs of arms are formed, or, in other words, each arm 17 is transversely aligned with an arm 18 to form a pair that functions to grip and convey a single length of pipe delivered to it by rack conveyor 12. The correct spacing of the arms is achieved and maintained by chains 26 (Figs. 4 and 5) which link the arms of each seriestogether in a manner to be described; these chains also being driven to provide the motive power for rolling the arms along tracks 23 and 24.

To drive chains 26, sprockets 27, 28, 29 and 31 (Fig. l) are provided, the chain for track 24 passing around sprockets 27 and 28, while the chain for track 23 passes 3 around sprockets 29 and 31. Motor 32 is the source of power for the apparatus, and, as seen in Fig. 1, its output is transmitted by a V-belt 33 to a variable speed unit 34, and from that unit by another V-belt 36 to a.

speed reducer 37 from which it is finally transmitted by belt 38 to horizontally and transversely extending drive shaft 39. On the ends of shaft 39 are mounted pinions 41 and 42 which mesh with bevel gears 43 and 44 mounted on the shafts of sprockets 27 and 29, so that the motor has direct driving connections only with these two sprockets.

As stated, the principal purpose of the invention is to carry pipe through a tank in which it is galvanized, and such a tank must provide a galvanizing circuit, or, in other words, a negative cathode, and a positive anode. Referring to Fig. 3, the anodes, preferably, are soluble metal balls 46 and 47, formed of Zinc, or the like, and carried in baskets 48 and 49 which, preferably, are formed of helically wound steel wire. To the outer ends of each of baskets 48 is secured a conductor 51 which is hooked over metal rods 52 that extend longitudinally from one end of the tank to the other. Similarly, to the outer ends of baskets 49 are secured hookshaped conductors 53 which engage metal rods 54 also extending the length of the tank. These rods 52 and 54, in turn, are suspended by bolts 56 that are secured to transverse, structural channels 57, of which there are a plurality, spaced longitudinally of the tank. Also, baskets 48 are connected together at their inner ends and they are provided central support by elongate bolts 58 also secured to channel 57, bolts 58 being split at their central portions to receive another metal rod 59, which is similar to rods 52 and 54.

Baskets 49, however, ditfer from baskets 48 in that .their inner ends rest on a platform 61, these inner ends being provided with loops or bails 62 adapted to be engaged by a suitable tool so that the inner ends of these baskets can be pulled upwardly out of the tank when the soluble zinc balls require replenishing. When the zinc balls of baskets 46 need replenishing, the outer or free ends of the baskets can be pulled upwardly simply by gripping the loops of wires 51 and pulling these free ends upwardly out of the bath, and, to permit lower baskets 49 to be pulled upwardly for replenishing, baskets 48 are staggered vertically with respect to baskets 49 throughout the length of the tank; it being appreciated that only one upper and one lower pair of these baskets are shown in Fig. 3, and that actually there are any number of such pairs carried by rods 52, 54 and 59 throughout the length of the tank. As will be understood, the positive current of the galvanizing circuit is supplied to the zinc balls through metal rods 52, 54, as well as conductors 51 and 53, and wire baskets 48 and 49.

The negative current for the galvanizing circuit is supplied by copper bus bars 63 and 64 which extend longitudinally of the tank as shown in Fig. 2 and which are disposed above the bath and near each tank side wall (Fig. 3). Also, as shown in Figs. 3 and 4, bus bars 63 and 64 are carried on a series of longitudinally spaced brackets 66 and 67, these brackets being bolted to and insulated from the top edges of tank side walls 2 and 3. Also, insulation is provided between the 'bus bars and their supporting brackets.

From bus bars 63 and 64, the negative current flows into pipe carrying arms 17 and 18, these arms having members which wipe against the bus bars as the arms travel through the tank. From the arms, the current flows into the length of pipe so that, as the pipe moves through upper and lower anode baskets 48 and 49, the galvanizing or electroplating takes place.

Plate carrying arms 17 and 18 are specially constructed and supported in the manner best seen in Figs. 3, 4 and 5. It has been pointed out previously that the arms are supported on tracks 23 and 24 by means of their roller 22. Tracks 23 and-24, in turn, are supported by 4 track-suspension brackets 68 and 69, brackets 68 being welded to transverse channel beams 57 and brackets 69 being welded to upper transverse beams 71. As will be seen in Fig. 2, downwardly inclined extents A of tracks 17 and 18, as well as their upwardly inclined extents C are unsupported by the transverse channel beams, but such support at these points is unnecessary. As to the specific construction of the arms, each mounts a pair of rollers 22 in a yoke member 72 which is centrally slotted at its lower portion to receive the upper end of a chain hanger member 73, this member being inserted into the slot and secured therein by means of a rivet 74 or the like. As has been stated, chains 26 hold the arms at the proper longitudinal spacing for forming transversely aligned pairs of arms to engage the opposite ends of the lengths of pipe. To achieve this, the upper portion of chain hangers 73 are inserted upwardly through the desired link of the chain and the chain hangers are made approximately the width of the link opening so as to prevent such play of the hanger in the links as would destroy this transverse alignment. Also, chain hangers 73 carry lugs 76 which press upwardly against the bottom of the links through which the hangers project, this arrangement clamping the links between the bottom edges of yoke 72 and the upper edges of lugs 76.

The lower portions of the arms carry the negative current to the pipe, and these portions are formed of channels 77 which, at their upper ends are bolted to and insulated from chain hangers 73. The mechanisms for contacting copper bus bars 63 and 64 are the wiper plates 78 which are carried by channel portions 77 of the arms and are spring-pressed outwardly by a coil spring 79 into flush engagement with the bus bars. The current from the bus bars is delivered to the arms through a conductor 81 and a connector 82, and as stated, this current flows downwardly and through the pins into the pipe. Also, it is preferable to sheath the lower portions of channels 77 with a rubber sheathing 83, or the like.

From the above description, it will be appreciated that the pipe-carrying arms are suspended in-a relatively freely swinging fashion, and this manner of suspension greatly facilitates the automatic loading and unloading of the pipe. However, before discussing the loading and unloading mechanism, it should be noted that as the arms pass through the tank, they are held against excessive swinging, which might release the pipe within the tank, by means of guide rails 84 (Fig. 3), these rails being supported by suitable braces welded to structural members of the apparatus.

Considering first the loading mechanism, it can be noted from Fig. 2 that as the transversely aligned pairs of arms commence their travel downwardly along inclined track extents A, each arm of the pairs is contacted by a cam the purpose of which is to spread or swing each pair of arms apart a sufiicient distance to permit a length of pipe to come between its pipe-carrying fingers. Accordingly, two cams 90 are provided, one being mounted so as to contact the inner side of arms 17 and the other to contact the inner sides of arms 18. Further, both cams are formed with beveled leading, or left, ends (Fig. 2) which the arms strike initially, and as the arms move along the cams they are pressed laterally outwardly to the desired extent. It is believed that such a cam will be readily understood, and that no further description is necessary.

After a pair of transversely aligned arms has been so spread, rack conveyor 12 moves a length of pipe into a position in which the pipe is aligned with the fingers of the arms, and, at this precise moment, plunger mechanism (Figs. 6 and 7) disposed at each side of the rack conveyor operates to press the transversely aligned arms one toward the other and insert the fingers of the arms into the pipe. The construction of rack conveyor 12 is best shown in Figs. 2, 6 and 7, and it consists of a set of four sprockets 91, 92, 93 and 94 around which a belt 96 travels, the belt carrying rack projections 97 between which the lengths of pipe are carried. The drive for the sprockets is takendirectly-from sprockets 28 (Fig. 1) and, for this purpose, sprocket-28'mounts a bevel gear 98 that meshes with apinion 99 mounted on a shaft 101. Also mounted on shaft 101 is a sheave 102 which has a belt connection with-another sheave 103 mounted on a shaft 104, this shaft104-beingthe one to which rack conveyor sprocket 91 is splined. It will be readily recognized that, by means of this rack conveyor drive, the rate of delivery of pipes by the rack conveyor can be closely co-ordinated with the speed of travel of the arm conveyors about their tracks, because both arm conveyors have a common source of power and the rack conveyor movement is controlled by the travel of the conveyor for arms 18.

The plunger arm loading mechanism is cam-operated and also is actuated by therotation of shaft 104- of rack conveyor sprocket 91 so that its operation is controlled by the rate of travel of the rack conveyor. As stated, a plunger mechanism is mounted in a suitable position at each side of the rack conveyor, and although only one such mechanism is illustrated in Figs. 6 and 7, it is believed that the manner in which both of these mechanisms are mounted and function should be clear. Referring to Figs. 6 and 7, it is seen that a cam wheel 106 is splined onto the end of rack conveyor sprocket shaft 104 and that this wheel contacts a cam roller 107 which is carried at the lower end of a pivotally mounted arm 108; this arm being pivotally carried on a suitable frame 109 secured to structural members of the apparatus. Frame 109 also is formed at its upper portion into a yoke 111 which provides bearings for a plunger 112. Also, the upper end of. pivotal arm 108 is secured to the plunger and, as seen in Fig. 6, the plunger normally is held in a retracted position by means of a coil spring 113. Cam wheel 106 is formed with suitable alternate protrusions so that, as it rotates, it alternately presses outwardly upon cam wheel 107 and thereby rocks arm 108 so as to move plunger 112 from its full line to its dotted line position and, when the wheel is not so pressed out wardly, the plunger returns to its full line position. Of course, the cam wheel projections are so formed and positioned that when the rack conveyor, which is operating in a timed relation with the arm conveyors, brings a length of pipe into alignment with the fingers of a pair of transversely aligned arms, the plunger is actuated to push the fingers into the ends of the pipe.

The pipe being supported on these fingers, the arms then continue their movement downwardly along track extents A to immerse the pipe in the tank, the pipe then being carried horizontally through the tank to receive its plating. Of course, the tracks and the length of the arms are so arranged that the pipe is carried through the electrolyte at a depth which places it between anode baskets 46 and 47 (Fig. 3). After the plating is completed, the arms commence their travel up track extents C, during which travel the arms are spread apart by cams 113 (Fig. 2) a sufficient amount to disengage the fingers from the pipe ends, whereupon the pipe drops freely onto a chute 114 which customarily leads to another conveyor that carries the plate pipe through subsequent washing tanks; this other conveyor and washing tanks forming no part of this invention.

The location at which the pipes are removed from the fingers is the unloading station of the apparatus. Cams 113 are similar to cams 90 in that they are arranged inside of the path of travel of the arms and are so formed that when a pair of arms strikes them, the arms are gradually pressed out due to beveled surfaces formed on thecams. Such a cam arrangement is an unusually simple manner of effecting release of the pipe, and its use is rendered possible due to the relatively freely swinging manner in which the arms are supported or suspended.

6. After the arms pass over the-cams, they swing back into their normal vertical position and travel along track extents D and back down track extents A torepeat the cycle.

It is believed that the operation of the various-mechanisms of the invention, as well'as the complete operative cycle of the endless conveying apparatus should be clear from the above description. One of the prin-' cipal' advantages of the apparatuslies in the simplicity with which the pipe is automatically picked up, carried through the electrolyte and'then released, this, as stated, being due primarily to the freely swinging, suspended pipe arms. Also, it is important to note that all the surfaces of the pipe receive the same amount of coating, since the lengths of pipe are gripped only by the narrow fingers which hook into and suspend the pipe. In contrast to this, other conventional practices require that the pipe be rolled along bus bars so that the surfaces contacting the bus bars may not receive sufiicient protective coating. Another important advantage which has been described is .the ability to closely co-ordinate the drive of the arm conveyors with the drive of rack conveyor 12 and also with the actuation of the arm loading plunger mechanism. This close co-ordination is an important factor in automatically loading the relatively long pipe carrying arms, since to insure engagement of the pins of the arms, the axis of the pipe must be aligned with the pins at the precise moment that the pins align With the plungers of the plunger mechanism. Further, the arrangement as a whole provides considerable flexibility insofar as varying the speed of the galvanizing operations in that it has been found that the rate of travel of the hanger arms can be varied from between about four to sixteen feet or more per minute. Other advantages, such as the structural simplicity and inexpensiveness, will be apparent to those skilled in this art.

According to the provisions of the patent statutes, I have explained the principle, preferred embodiment and mode of operation of my invention, and have illustrated and described what is now considered to represent its best embodiment. However, I desire to have it understood that, within the scope of the appended claims, the invention may be practised otherwise than as specifically illustrated and described.

I claim as my invention:

1. In electro-plating apparatus for pipe and conduits, a tank adapted for holding an electrolyte, an arm engaging one end of a length of pipe for supplying electric current to the pipe, the portion of the arm that engages the pipe being located within the tank and intermediate the bottom and top thereof, a complementary arm supporting the other end of the length of the pipe and having its portion that engages the pipe located within the tank and intermediate the bottom and top thereof, the arms being movable individually with swinging movement transversely of the tank, similar arms engaging other lengths of pipe within the tank, insulation surrounding the arms from a location close to the regions of engagement of the arms and pipes and for a substantial distance upward on said arms, separate mechanism above the top of the tank for supporting and moving the arms on the different ends of the pipes and including a track and roller movable thereover and in directions lengthwise of the tank, a bus bar adjacent to the arms on at least one side of the tank and on the sides of the adjacent arms opposite to the sides toward the pipes, the bus bar being at an elevation above said predetermined level of the tank and at a substantially lower level than the supporting mechanism, the bus bar extending in the direction of movement of the arms by said mechanism, and each of the current carrying arms on one side of the tank having a contact surface on its side opposite the portion of the arm that engages the pipe and in position to bear against the bus bar as the arm is moved lengthwise of the tank whereby the bus bar holds the arms against the 8 swinging away from the ends of the pipes that the arms References Cited in the file of this patent support.

2. In the electro-plating apparatus described in claim UNITED STATES PATENTS 1, a combination in which there are bus bars on both 799,402 Potthofi p 12, 19 sides of the tank on the opposite sides of the current- 5 ,33 ,0 2 Pingcr Apr. 6, 1920 carrying arms from the ends of the pipes 011 that side 68, 5 D pcrnell July 15, 1932 of the tank, and there is a contact on each of the current- 7, Loney O t. 16, 1945 carrying arms in position to bear against the bus bar, and 2,60 ,535 Laney June 24, 1952 spring means between each contact and its current carry- 2, 75,813 Kenne y Apr. 20, 1954 ing arm urging the contact against the bus bar and 10 urging the arm toward the pipe end. 

1. IN ELECTRO-PLATING APPARATUS FOR PIPE AND CONDUITS, A TANK ADAPTED FOR HOLDING AN ELECTROLYTE, AND ARM ENGAGING ONE END OF A LENGTH OF PIPE FOR SUPPLYING ELECTRIC CURRENT TO THE PIPE, THE PORTION OF THE ARM THAT ENGAGES THE PIPE BEING LOCATED WITHIN THE TANK AND INTERMEDIATE THE BOTTOM AND TOP THEREOF, A COMPLEMENTARY ARM SUPPORTING THE OTHER ENF OF THE LENGTH OF THE PIPE AND HAVING ITS PORTION THAT ENGAGES THE PIPE LOCATED WITHIN THE TANK ANDINTERMEDIATE THE BOTTOM AND TOP THEREOF, THE ARMS BEING MOVABLE INDIVIDUALLY WITH SWINGING MOVEMENT TRANSVERSELY OF THE TANK, SIMILAR ARMS ENGAGING OTHER LENGTHS OF PIPE WITHIN THE TANK, INSULATION SURROUNDING THE ARMS FROM A LOCATION CLOSE TO THE REGIONS OF ENGAGEMENT OF THE ARMS AND PIPES AND FOR A SUBSTANTIAL DISTANCE UPWARD ON SAID ARMS, SEPARATE MECHANISM ABOVE THE TOP OF THE TANK FOR SUPPORTING AND MOVING THE ARMS ON THE DIFFERENT ENDS OF THE PIPES AND INCLUDING A TRACK AND ROLLER MOVABLE THEREOVE AND IN DIRECTION LENGTHWISE OF THE TANK, A BUS BAR ADJACENT TO THE ARMS ON AT LEAST ONE SIDE OF THE TANK AND ON THE SIDES OF THE ADJACENT ARMS OPPOSITIE TO THE SIDES TOWARD THE PIPES, THE BUS PAR BEING AT AN ELEVATION ABOVE SAID PREDETERMINED LEVEL OF THE TANK AND AT A SUBSTANTIALLY LOWER LEVEL THAN THE SUPPORTING MECHANISMM THE BUS BAR EXTENDING IN THE DIRECTION OF MOVEMENT OF THE ARMS BY SAID MECHANISM, AND EACH OF THE CURRENT CARRYING ARMS ON ONE SIDE OF THE TANK HAVING A CONTACT SURFACE ON ITS SIDE OPPOSITE THE PORTION OF THE ARM THAT ENGAGES THE PIPE AND IN POSITION TO BEAR AGAINST THE BUS BAR AS THE ARM IS MOVED LENGTHWISE OF THE TANK WHEREBY THE BUS BAR HOLDS THE ARMS AGAINST THE SWINGING AWAY FROM THE ENDS OF THE PIPES THAT THE ARMS SUPPORT. 